Sipex DAC 9377-16 no longer sold, but TI DAC712 will serve

[William Beaty]

The Sipex DAC9377-16-4 has a strange aging problem: resistors in the ladder will drift in value until the analog output is not only non-linear, but entirely crazy.



DAC 9377 is common in hospital NMR, military simulators, and older custom research instruments. (If it ran any proportional hydraulics in manned simulators, they'd be in for an increasingly rough ride over the years.) The old chips are expensive if you can find them at all, and of course may suffer the same aging problem.

So, build yourself an adapter-board to match Texas Inst DAC712 pinout. See link below. Needs one signal inverted, pullup/gnd of mode pins, and zero/gain trimmers on board. See:

http://staff.washington.edu/wbeaty/chem_sipex9377.html

 

[N_Cook]

William Beaty <billb@eskimo.com> wrote in message
news:84e31fef-b553-487b-8c5c-81e8838a6f54@googlegroups.com...
The Sipex DAC9377-16-4 has a strange aging problem: resistors in the ladder
will drift in value until the analog output is not only non-linear, but
entirely crazy.



DAC 9377 is common in hospital NMR, military simulators, and older custom
research instruments. (If it ran any proportional hydraulics in manned
simulators, they'd be in for an increasingly rough ride over the years.)
The old chips are expensive if you can find them at all, and of course may
suffer the same aging problem.

So, build yourself an adapter-board to match Texas Inst DAC712 pinout. See
link below. Needs one signal inverted, pullup/gnd of mode pins, and
zero/gain trimmers on board. See:

http://staff.washington.edu/wbeaty/chem_sipex9377.html


+++++
ah! , fuzzy logic
So what is the reason for the Rs drifting? surely not heat-induced chemical
change which is the usual reason.